Respuesta :

Answer:

[tex] 10 {x}^{2} + 2x - 9[/tex]

Step-by-step explanation:

[tex](3 {x}^{2} + 2x - 5) + ( - 4 + 7 {x}^{2}) \\ = 3 {x}^{2} + 2x - 5+ 7 {x}^{2} - 4 \\ = 3 {x}^{2} + 7 {x}^{2} + 2x - 5- 4 \\ = 10 {x}^{2} + 2x - 9[/tex]